In 2001, your choice of hybrid cars in the United States was limited to two models: the Honda Insight and the Toyota Prius. By 2010, you could pick from 27 models of cars that used both a gasoline engine and an electric motor for greater fuel efficiency. Come 2015, about 55 different hybrids are expected to be available [source: HybridCars.com].

Hybrids have arrived. Early models might have appealed largely to the greener-than-thou crowd or serious techies, but as hybrid versions of popular cars like the Honda Civic and the Toyota Camry have appeared, interest has definitely gone mainstream. More than 290,000 hybrids were sold in the United States in 2009 [source: HybridCars.com]. And if the government, as some expect, boosts the mileage requirements for U.S. fleets to 60 miles per gallon by 2025, hybrids are bound to play a part in our auto future [source: HybridCars.com].

There are reasons why hybrids are appealing to a wider audience. Their mileage is increasing: The first-generation Prius chalked up a combined mileage of 41 miles per gallon; by 2010 it was getting 50 miles per gallon [source: Vijayenthiran]. To attract buyers, car makers often fit hybrids with luxurious interiors and all the latest gadgets. As a bonus, the cars now boast better performance and faster acceleration.

How do you decide if a hybrid is right for you? Which one do you want? Because it's a rapidly developing technology, choosing a hybrid takes some thinking. Read on for five tips that will help you make an informed hybrid decision.

5

Focus on Why You're Buying

Knowing why you're buying a hybrid makes your decision easier. Some buyers want to save money, but savings aren't always easy to calculate. Most hybrids cost more than comparable gasoline-only models. Calculating whether savings on fuel will make up for this premium requires some investigation.

For example, a 2010 Honda Civic hybrid cost $3,281 more than its equivalent gas model and saved an average driver $432 a year in fuel costs. That's a 7.2 year payback period. A Toyota Camry hybrid, with a much smaller premium, pays back the difference in only 1.3 years [source: Fallon]. Keep in mind that if fuel prices rise or you drive more miles each year, the payback period shrinks.

Saving bucks is not the only reason to opt for a hybrid. Plenty of buyers are interested in reducing emissions. An ordinary Civic emits 6.3 tons of greenhouse gases a year, while a hybrid version only puts out 4.4 tons [source: Clarke].

Maybe you are looking for cutting-edge technology -- hybrids are definitely high tech. Maybe you want to reduce dependence on foreign oil. If all Americans drove hybrids, the United States would use about 15 percent less gas overall [source: CarBuyingTips.com]. Or maybe you've just fallen in love with the vehicle's look or design. Knowing your motivation for buying will point you toward the features you want in a hybrid.

The Hybrid Price Premium

Hybrids have typically cost $2,000 to $5,000 more than comparable models. But in 2010, Lincoln introduced its MKZ luxury hybrid without any premium over the nonhybrid version [source: Motavalli]. This may be the beginning of a trend that will encourage other car makers to follow suit.

4

Educate Yourself

What is a hybrid? It's a vehicle that uses more than one source of energy for power. Typically it's a gasoline internal combustion engine and electric motor. But there are other wrinkles to consider.

In series hybrids, the gas engine drives a generator that charges the batteries for the electric motor.

Parallel hybrids are cars in which both the engine and the motor can drive the wheels.

In mixed hybrids, the most common type, the gas engine can either generate electricity or power the car directly.

Full hybrids have an electric motor powerful enough to start the car from a stop and take it to full speed.

In mild hybrids, the electric motor is small, more of a booster.

How much fuel do hybrids save? The Toyota Camry hybrid is rated at a combined city/highway mileage of 34 miles per gallon, versus a regular Camry at 26 miles per gallon. The Honda Civic Hybrid gets 42 miles per gallon; the gasoline-only Civic gets 29 miles per gallon [source: Fueleconomy.gov].

Research the different types of hybrids available. They range from compact cars to full-sized sedans to hefty SUVs. They can be almost as powerful as you want -- the Lexus GS 450h generates 300 horsepower [source: CarsDirect].

Don't ignore the next wave of hybrid technology, the plug-in hybrids. These vehicles typically have a larger battery and can be recharged by connecting them to a source of electricity. (Ordinary hybrids never need to be plugged in.) This option saves even more gas. The cars are starting to become available now, and Toyota plans a plug-in Prius in 2012.

Not a New Idea

Why didn't automakers think of hybrids a long time ago? They did. The first hybrid prototype was developed by Ferdinand Porsche in 1900. Inventor Henri Pieper was awarded the earliest U.S. hybrid patent in 1909.

3

Look at Alternatives

Hybrids are not the only game in town. Before you buy, consider other ways you could achieve your goals.

Some gasoline-only vehicles are nearly as efficient as hybrids. You could choose a little Smart ForTwo that gets 33 miles per gallon in the city and 41 miles per gallon on the highway. Or a Toyota Yaris (29/36 miles per gallon) [source: Shapley]. Diesel is another alternative. Two clean-diesel cars are among the top 10 most fuel efficient.

All-electric vehicles are about to appear on the market. They do away with the gasoline engine altogether. The Nissan Leaf, for example, can go 100 miles on a single battery charge. All-electrics may be better than hybrid for some drivers.

By simply changing driving habits, you can save fuel with any vehicle, conserving gas and shrinking your carbon footprint in the process. Avoiding rapid acceleration is one technique. Simply driving 65 mph on the highway instead of 75 can increase mileage by 14 percent [source: Reed]

Driving your old car another 20,000 miles might save more emissions than purchasing even the most fuel-efficient new one by sparing the carbon released during the mining, refining of the steel and the manufacturing of the other components. And if reducing emissions is your main goal, consider taking public transportation, carpooling or bicycling.

The 100 MPG Car

The Edison2 prototype can run for 100 miles on a gallon of gas, carry four passengers and meet safety standards. No, it's not a hybrid. For ultra-mileage, batteries are far too heavy. This extremely light vehicle uses a motorcycle-sized gasoline engine for power [source: Lamb].

2

Match Your Driving Style

Standard vehicles get better mileage on the highway than in stop-and-go city driving. Hybrids give you the biggest savings when you're inching along in a traffic jam. The reason is that at low speeds, hybrids use mainly the electric motor. They shut down the gas engine entirely when stopped. A regular car keeps idling, achieving 0 miles per gallon.

At high speeds, hybrids rely more on their gas engines. So a driver who has a long daily commute on the open road will not get as much benefit from a hybrid as one who mainly takes short trips around town.

Driving style makes a big difference as well. Rapid acceleration and higher speeds reduce hybrid fuel savings. For example, a Honda Insight hybrid gets 39 miles per gallon when driven by a lead-footed driver, but offers the slower, conservative driver 51 miles per gallon [source HybridCars.com].

Fortunately, hybrids make it easier to change the way your drive. Most come with dashboard monitors that let you keep an eye on how your driving is affecting your mileage. Some offer economical driving modes that let you trade acceleration for fuel savings.

Another Form of Energy Storage

A hybrid's batteries are charged in part by absorbing energy generated when you brake. Experimenters are investigating an even more efficient way to store energy: a compact, high-speed flywheel. Rotating tens of thousands of times a minute, the device smoothly absorbs energy and returns it to the wheels for accelerating [source: Professional Engineering].

1

Consider the Incentives

In order to boost the market for hybrids, the U.S. federal government offered tax credits to offset their purchase beginning in 2005. The catch was that it applied only to the first 60,000 hybrid vehicles sold by each manufacturer. Some car makers have surpassed that limit.

New federal incentives are available for plug-in hybrids. They range from $2,500 to $7,500 depending on battery size. It definitely pays to shop around for incentives, which can make a hybrid much more affordable or attractive. Some additional incentives:

Various states offer their own income tax credits for hybrid purchases.

There's a federal tax credit that covers 50 percent of the cost of a plug-in hybrid charger.

Some cities allow hybrids to park for free in municipal lots.

Retailers like Whole Foods and Home Depot offer preferred parking at some stores.

Some cities allow single-passenger hybrids to travel in car-pool lanes.

Checking out all the incentives takes some digging, but together they may make or break your hybrid purchase decision.

Employers Reward Hybrid Owners

Some companies give worker incentives to purchase or drive hybrid cars. Google, for example, offers employees a $5,000 subsidy for buying a vehicle that gets 45 miles per gallon or higher. Integrated Archive Systems, a company in Palo Alto, Calif., gives workers a $10,000 subsidy for a hybrid purchase [source: HybridCars.com].

Hybridcars.com. "White House May Seek to Set 2025 CAFÉ Standards as High as 62 MPG," Oct. 1, 2010. (Oct. 21, 2010)http://www.hybridcars.com/news/white-house-may-seek-set-2025-cafe-standard-high-62-mpg-28660.html